| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.22 | 1.33 | 1.12 |
| 2024 | 1.22 | 1.41 | 1.02 |
| 2023 | 1.29 | 1.66 | 1.08 |
| 2022 | 1.66 | 2.14 | 1.26 |
| 2021 | 2.23 | 3.23 | 1.64 |
| 2020 | 1.34 | 1.88 | 0.92 |
| 2019 | 1.5 | 2.61 | 1.26 |
| 2018 | 2.28 | 3.85 | 1.29 |
| 2017 | 1.42 | 2.7 | 0.94 |
| 2016 | 0.98 | 1.41 | 0.81 |
| 2015 | 1.72 | 3.33 | 1.21 |
| 2014 | 1.02 | 1.43 | 0.88 |
| 2013 | 1.14 | 1.4 | 0.91 |
| 2012 | 1.37 | 1.84 | 0.92 |
| 2011 | 2.42 | 4.91 | 1.62 |
| 2010 | 2.52 | 3.19 | 1.89 |
| 2009 | 2.25 | 3 | 1.65 |
| 2008 | 2.74 | 4.64 | 1.36 |
| 2007 | 3.27 | 5.02 | 1.61 |
| 2006 | 1.84 | 2.81 | 1.07 |
| 2005 | 1.26 | 1.66 | 0.99 |
| 2004 | 1.61 | 1.98 | 1.39 |
| 2003 | 1.87 | 2.47 | 1.43 |
| 2002 | 2.43 | 2.66 | 1.91 |
| 2001 | 3.14 | 3.78 | 2.31 |
| 2000 | 4.25 | 4.76 | 3.48 |
| 1999 | 4.27 | 5.66 | 3.36 |